The Channel is the name given to the stretch of water which

The Channel is the name given to the stretch of water which separates England and France. Ferries operate all year round to carry people across the Channel, and they are busy most of the year. January is the only quiet month nowadays. As well as summer holiday-makers, there are day trippers and coach traffic, not to mention lorries and other commercial vehicles. Some ferries carry cars and their passengers, while others also connect train passengers with the Continental rail network.
The biggest hazard for the ferry is the wind. The crew listens to BBC weather reports four times a day. Or they sometimes get gale warnings from local radio station.
Crossing the Channel by ferry is a bit like trying to cross Oxford Street on a busy afternoon, according to one ferryboat captain. The ferries from Folkstone and Dover to Calais and Boulogne have to cross the main flow of traffic. This consists of ships traveling through the Channel to and from Northern Europe. There may be four hundred ships making the journey at any one time, and they all pass through a “choke point” which is only fifteen miles (twenty-five kilometers) wide. The cross-channel ferries have to sail right through the middle of all this traffic.
68. The passage is mainly concerned with _____.
A. the English Channel B. the weather on the Channel
C. cross-channel ferries D. what crossing the Channel by ferry is like
69. The word hazard is closest in meaning to ________.
A. trouble B. danger C. enemy D. problem
70. We can infer from the passage that _______.
A. if there is a gale warning from the BBC, the ferries will stop operating.
B. the traffic on the Channel is very busy only in winter
C. ferries are busiest in the afternoon
D. the crew of the ferry listens to the weather reports four times a day
71. Where does this passage most probably appear?
A. In a dictionary. B. In a novel.
C. In a transportation magazine. D. In a geography textbook.